Anoectochilus spp. belong to Orchidaceae, wherein Anoectochilus formosanus Hayata is regarded as “the king of medicines” by the Taiwanese because of its diverse pharmacological effects, such as reducing blood pressure and blood sugar levels, hepatoprotection, and enhancing immunity. Therefore, Anoectochilus formosanus Hayata has generally been used as a folk medicine for treating liver fibrosis, diabetes and cardiovascular diseases.
The crude extracts of Anoectochilus formosanus Hayata have several pharmacological effects, such as antiosteoporosis (Shih C C et al., J Ethnopharmacol, 2001, 77: 233-228), antihyperglycemic effect (Shih C C et al., Clin Exp Pharmacol Physiol, 2002, 29: 684-688.; JP7076522), lipid-lowering effect (JP 6293655), improving memory and learning (Cheng H Y et al., J Chin Med, 2003, 14: 235-245.), inhibiting the oxidation of LDL (Shih C C et al., Am J Chin Med, 2003, 31: 25-36.), and treating tumors (U.S. Pat. No. 7,033,617). In addition, Lin et al. showed that Anoectochilus formosanus Hayata has hepatoprotective effects on carbon tetrachloride (CCl4)—or acetaminophen-induced acute hepatitis (Lin J M et al., Am J Chin Med, 1993, 11: 59-69; Lin C C et al., Am J Chin Med, 2000, 28: 87-96). Du et al. also showed that aqueous extracts of Anoectochilus formosanus Hayata inhibited cell damage induced by CCl4 in primary cultured rat hepatocytes (Du X M et al., Phytother Res, 2003, 17: 30-33). Recently, it was also shown that an aqueous extract of Anoectochilus formosanus Hayata attenuated hepatic fibrosis induced by both CCl4 and dimethylnitrosamine in rats (Shih C C et al., Clin Exp Pharmacol Physiol, 2004, 31: 620-625; Shih C C et al., Phytomedicine, 2005, 12: 453-460).
Thus, the research has shown that Anoectochilus formosanus Hayata has an hepatoprotective effect. Since this herb is highly regarded in the Taiwanese herb market and cannot be colonal propagated quickly enough to sustain its uses, its prevalence in nature has depleted substantially. Although the vegetative propagation of Anoectochilus formosanus Hayata using tissue culture and modified cultivation of Anoectochilus spp. root have been achieved (Shiau Y J et al., Bot Bull Acad Sin, 2002, 43: 123-130; JP10056875(A)), only limited amounts of Anoectochilus spp. can be produced. Therefore, if the hepatoprotective compound(s) in Anoectochilus formosanus is(are) identified, the hepatoprotective preparations containing the compound(s) will be provided via synthesized and large-scale production.
The purpose of the present invention is to identify the major active compounds from Anoectochilus formosanus Hayata from both in vivo and in vitro experiments. Additionally, a fraction from Anoectochilus formosanus Hayata adverse to liver is also identified.